Direct motor drive for agitator and spin tub



March 31, 1970 R. E. LAKE .3,503,228

DIRECT MOTOR DRIVE FOR AGITATOR AND SPIN TUB Filed July 8, 1965 4 Sheets-Sheet 1 dal' I NVEN TOR.

forse/ ,6: afg E'r-*g I BY .4 y@ MKM f ATTORNEYS March 3l, 1970 R. E. LAKE 3,503,228

DIRECT MOTOR DRIVE FOR AGITATOR AND SPIN TUB Filed July 8, 1965 4 Sheets-Sheet 2 INVENTOR. Poef ,6: ake' March 31, 1970 R. E. LAKE 3,503,228

DIRECT MOTOR DRIVE FOR GITATOR AND SPIN TUB Filed July 8, 1965 4 Sheets-Sheet 5 72 *LI-1L- 7/ W- IL: 2 E25.. m

1-I f O n INVENTOR.

A T RNE YS R. E. LAKE: 3,503,228

DIRECT MOTOR DRIVE FOR AGITATOR AND SPIN TUB March 31, 1970 4 Sheets-Sheet 4 Filed July 8, 1965 INVENTOR. az@

ATTO EYS United States Patent 3,503,228 DIRECT MOTOR DRIVE FOR AGIIATOR AND SPIN TUB Robert E. Lake, Benton Harbor, Mich., assignor to Whirlpool Corporation, St. Joseph, Mich., a corporation of Delaware Filed July 8, 1963, Ser. No. 293,420 Int. Cl. D06f 33/02, 37/04, 23/04 U.S. Cl. 68-12 3 Claims This invention relates generally to a method and apparatus for cleaning or drying articles to be laundered or dry cleaned, such as clothes, wherein rotatably or oscillatably operable components of the apparatus are driven by an induction-type motor having a plurality of poles terminating in a plane adjacent the surface of a member or part disposed radially Of the axis and in circumferentially spaced relation, thereby producing a moving magnetic eld for inducing the required movement of the member.

In cleaning appartaus heretofore provided it is customary to provide a treatment zone in which materials to be cleaned are mechanically agitated in the presence of a cleaning agent such as a laundry liquid. In vertical axis machines, the agitation is customarily provided by an agitator which oscillates within a basket or receptacle and in such apparatus, the basket or receptacle is frequently made rotatable so that an extraction operation can be effected with respect to the materials being cleaned in the same container.

ln horizontal axis machines, a rotatable basket or container is generally provided which can be rotated either at a tumbling speed in order to subject the materials to a cleaning or drying action or at a higher centrifuging speed for extraction purposes.

With such prior art apparatus, it is customary to include some form of a driving motor linked to the movable parts of the apparatus by a speed-changing means. Oftentimes the speed-changing devices are complicated and cumbersome and may include complex gear trains and transmissions or a multiplicity of pulleys and other devices which permit a single driving motor to deliver the motive power for effecting the multiple speed driving actions required for either actuating an agitator or operating a drum at tumbling speed and for spinning a container or basket at a centrifuging speed.

In accordance with the present invention, it is contemplated that the customary electric motor as conventionally employed and the usual speed-changing means would all be eliminated, and the motive power for effecting the necessary movement of the movable components is provided by a so-called arcuate or linear induction motor wherein a plurality of poles terminate in a plane adjacent the surface of a driving part or member in circumferential or arcuate spaced relation and radially outwardly of the axis of the movable part. Thus, a moving magnetic eld is produced which induces av corresponding movement of the surface and hence of the part.

A very important advantage of this arrangement is that the required drive power can be produced at a very low operating speed without substantially increasing the physical size or mass of the eld structure of the motor and without any substantial decrease in efficiency. rIllus no speed reducing mechanism is required. The low operating speed arises from the fact that the synchronous speed of operation in revolutions per minute is equal to the product of the effective angular spacing of poles in degrees and the frequency in cycles per second, divided by a constant which is 3 in the case of a single phase motor, and with the linear induction motor, it is possible to have lCC a very small angular spacing between poles to thus produce a correspondingly low synchronous speed of operation. The actual speed is somewhat less than the synchronous speed due to the slip which obtains in the normal operation of an induction type motor. An additional advantage is in a compact physical relationship of the motor structure to the agitator and receptacle structure of the cleaning apparatus. Another advantage is that a reciprocating action can be readily produced, through the use of reversing circuitry of a relatively simple nature. Further, by electronically controlling the energization of the motor, infinitely variable speeds may e afforded.

It is, therefore, an object of the present invention to provide a cleaning apparatus wherein a movable part thereof is driven by a so-called linear induction motor.

It is a further object of the present invention to provide a laundry machine of either the vertical or horizontal axis type wherein the rotatable or oscillatable members thereof are driven in a rotary or oscillatory motion by a disk motor of the linear induction type,

A further object of the present invention is to provide a laundry machine wherein agitator means are driven by a linear induction-type motor.

A still further object of the present invention is to provide a laundry machine using as its prime mover for the agitating and centrifuging components thereof a linear induction-type motor and wherein electronic control of the motor will afford variable operating conditions as required in a cleaning cycle.

Yet another object of the present invention is to provide a laundry machine wherein a conventional motor and speed-changing means such as a gear case or pulley means is eliminated in favor of a linear induction-type motor.

Many other features, advantages and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description which follows and the accompanying sheets of drawings in which a preferred structural embodiment of a cleaning apparatus such as a vertical axis machine or a horizontal axis machine is shown by way of illustrative example and which is capable of practicing the inventive methods contemplated by the present invention.

On the drawings:

FIGURE l is an elevational view of an automatic laundry machine constructed in accordance with the principles of the present invention with parts of the cabinet therefor broken away and with certain other parts in vertical section;

FIGURE 2 is a side elevational view of a horizontal axis type laundry machine with parts of the casing broken away to illustrate features of the invention;

FIGURE 3 is an enlarged fragmentary view 0f a portion of the subject .matter shown in FIGURE l partly in section showing additional details of construction of the arcuate linear induction-type motor utilized in accordance with the principles of the present invention and parts are shown in section taken in the plane of line III-III of FIGURE 5;

FIGURE 4 is a fragmentary cross-section taken on line IV-IV of FIGURE 5 and illustrates additional details of the stator;

FIGURE 5 is a fragmentary elevational view taken in the plane of line V-V of FIGURE 3 and showing additional details of the stator; and

FIGURE 6 is a schematic view showing a portion of the structure of FIGURE l in cross section and illustrating a portion of the structure in bottom plan and further illustrating a circuit diagram for the electronic control 3 circuitry associated with the linear induction motor of the present invention.

As shown on the drawings:

It will be understood that the principles of the present invention are applicable to any cleaning apparatus wherein movable components are actuated or driven such as domestic and commercial laundry apparatus, drycleaning machines, dishwashers and other forms of cleaning appliances. For purposes of illustration, however, the present invention is shown as embodied in a laundry appliance such as a vertical axis washing machine, shown generally in FIGURE 1, or a horizontal axis laundry machine, as shown in FIGURE 2.

In the embodiment of the invention illustrated in FIG- URE 1, there is shown an automatic Washing, rinsing and drying machine designated generally at having a cabinet 11 forming an enclosure for a tub 12 constituting a treatment zone 13 for clothes or other fabrics to be laundered in uid retained in tub 12.

In order to retain clothes within the treatment zone 13, there is provided a receptacle or basket forming a clothes container 14 which is rotatably mounted within the tub 12 and which is closed at its top by the cabinet 11 which also forms an enclosure for the entire control and driving mechanism of the apparatus.

The tub 12 is shown as being carried on a oating base 16 suspended from the top portion of the cabinet on three suspension links 17 incased in rubber at their ends and carried in sockets 19 in the base 16.

An oscillatable drive shaft 20 is shown as being journaled in a bearing 21 and extending upwardly through the base 16 and into the interior of the tub 12 wherein the shaft 20 is journaled within a rotatable drive sleeve 22. The sleeve 22 extends Within a stationary sleeve 23 which extends upwardly from a hollow center post 24 secured in rm and sealed assembly with the bottom wall of the tub 12 by a plurality of fasteners 26.

The hollow center post 24 not only forms a closure for the center part of the bottom of the tub 12, but also extends upwardly from the bottom of the tub 12 and supports the stationary sleeve 23 which provides a support for the basket or container 14. The top support means is indicated generally at 27 and it will be noted that the inner upstanding portion of the container or basket 14 is shown at 28. An agitator 29 is carried on the upper end of the shaft 20 and is suitably secured thereto so as to be driven in unison with any movements imparted to the shaft 20.

The sleeve 22 extends downwardly along the length of the shaft 20 and is adapted to be rotatably driven, thereby to correspondingly drive the basket or container 14.

Although the principles of the present invention are applicable to any vertical axis laundry machine such as a vertical axis machine of the so-called overflow rinse type, the present embodiment shows a perforated basket 14 having foraminous walls with openings 30 embodied therein. Thus, although the features of the plumbing arrangements are not necessary to the understanding of the present invention, it will be appreciated that iluid can be pumped to and from the treatment zone 13 and will be confined by the tub 12.

In order to automatically operate the machine 10 through a programmed sequence of washing, rinsing and drying periods, a presettable sequential controller is shown generally at 31 and includes a presettable adjustment knob 32 which may be manipulated by the operator of the machine in order to preselect the desired program, thereby to automatically operate the machine 10 through a cleaning sequence.

Turning now to FIGURE 2, a horizontal axis laundry machine 33 is illustrated comprising a casing 34 having a front wall 36 in which is formed an opening 37 closed by an axis door 38.

The casing 34 provides an enclosure for a tub forming a treatment zone 39 and having a rear bulkhead 40.

In order to confine a batch of materials to be laundered or processed Within the treatment zone 39, there is provided a drum or receptacle 41 having a foraminous outer cylindrical wall formed with openings 42 and carried by inleans of a cantilever support arrangement on the end of a shaft 44 journaled in a bearing assembly 46.

The drum 41 has an opening 47 formed in register with the door 38 through which the materials to be laundered may be inserted and removed.

The machine is provided with a presettable sequential control means 48 having a presettable adjustment knob 49 by means of which the machine may be automatically operated through a programmed sequence of washing, rinsing, extracting and drying operations since it will be appreciated that the machine 33 may constitute either an ordinary laundry machine or a so-called combination ywasher-extractor or combination washer-dryer wherein clothes may be selectively washed, rinsed and dried, or merely dried or merely washed.

In accordance with the principles of the present invention, the movable components of the apparatus exemplified by the machines 10 and 33 are to be driven by a linear induction-type motor. In this regard, the structural components and the principles involved are generally similar and for ease in convenience in understanding the principles of the present invention, common reference numerals will be applied to illustrate like components on both machines 10 and 33.

The ordinary induction motor, of course, is the most common type of electric -motor in commercial use on cleaning apparatus and generally consists of an outer case surrounding a stator wherein the magnetic poles terminate in a circle radially outwardly of a rotor connected to a driven shaft. By supplying the windings of the poles with alternating current the current supply permits the various electrical eld magnets to reach maximum strength in a sequence and the magnetic eld inside the set of magnets effectively rotates through one complete revolution in every cycle of the A.C. supply. Thus, when the rotor is placed inside of the magnetic system, the moving magnetic field induces a current in the electrically conducting metal and the current is then itself acted upon by the same eld which produced it so that a torque is exerted. on the cylinder and rotation is produced. The rotating eld has the effect of exerting a torque on the rotor which is rotatably disposed therewithin. Where the rotor consists of bars firmly assembled between end pieces, the rotor is sometimes referred to as a squirrel-cage.

In accordance with the principles of the present inven'- tion, an induction-type motor is utilized; however, the stator is, in effect, opened up so that a plurality of poles terminate in a plane rather than in a circle as in a conventional motor.

To characterize such basic difference, the motor of' the present invention as utilized in the cleaning apparatus of the present invention will be referred to as a linear induction motor. Thus, in the linear induction motor arrangement of the present invention, the movable component of the cleaning equipment has a driven portion thereof disposed in a plane perpendicular to the axis of movement. Such portion may constitute a disk-like member which is connected in corotatable assembly with the movable part or with the shaft thereof. Depending upon its use as an oscillatory or rotary drive system, this disk portion may be of a segmental configuration or of a circular' shape. The plural poles of the stator are then terminated adjacent the surface of the driven disk in circumferentially or arcuately spaced relation to one another and perpen-y dicular to the axis of rotation or oscillation. Thus, the windings on Vthe stator will produce a moving magnetic eld which induces a current in the electrically conductive metal of the disk and since the current is then acted upon by the same eld which produced it, a torque will be exerted on the disk and since such torque acts through a moment arm by virtue of being spaced radially outwardly of the axis, a movement of the movable oscillatable or rotatable member will be produced.

As shown in FIGURE l, the shaft 20 associated with the agitator 29 has connected therewith a disk 50 which is disposed in the radial plane perpendicular to the axis of rotation of the shaft 20. The sleeve 22 likewise has a disk 51 attached thereto which is disposed in a radial plane perpendicular to the axis of rotation of the sleeve 22 which rotates in unison with the tub or container 14.

For details of such construction, reference may be made to FIGURE 6 wherein the shaft 20 is shown connected to a hub 53 which in turn is connected to the disk 50 by a plurality of fasteners 54.

The sleeve 22 has a hub 56 connected thereto by a set screw 57 and the disk 51 is connected in corotatable assembly with the hub 56 by a plurality of fasteners 58.

A stator for each linear induction motor unit is carried by a bracket assembly including appropriate hanger bars indicated at 60 which may be fastened, in the case of the machine 10, to the base 16 as at 61 (FIGURE 3) and, in the case of the machine 33, to the rear bulkhead 40 (FIG- URE 2) by similar parts 60a and 61a. Other parts of the illustrative structure in FIGURE 3 which correspond in general function to structure in FIGURE 1 are also designated by the sufx af Each motor unit includes a magnetic field structure 62 having poles and windings thereon, and a member 63 of magnetic material on the opposite side of the disk, for producing a moving field of high intensity in the disk. The structures 62 and members 63 are provided with openings 64 through which suitable fastening means 66 extend to hold the parts in firm assembly with one another. Spacer sleeves 67 are inserted between the first and second parts to facilitate the proper spacing relationship.

The disks 50 or 51 are preferably made of nonmagnetic electrically conductive material such as aluminum, and the disks 50 and 51 are particularly characterized by a reduced peripheral portion shown at `68 and 69, respectively, In the case of a domestic laundry appliance having the proportions of the machines and 33, the thickness of the peripheral portions 68 and 69 would be inthe range of about .C30-.040 inch.

Details of the field structure 62 are shown in FIGURES 4 and 5 and it will be noted that each structure 62 has a body portion 70 and a plurality of pole pieces which are T-shaped in cross section, each including a major leg 71 and laterally extending minor legs 72 and 73.

Field windings are wound around the leg 71 of the poles as at 74. All of the legs 72, 73 are disposed in coplanar relation and are arranged to extend in a circumferential row in closely spaced relation to the reduced portion 68 or 69 of the respective disks 50 and 51.

Where two linear induction motor units are provided, the support rods 60 may be `provided with extensions as at 76 in FIGURE 3, thereby to dispose the units in a stacked relation.

As illustrated by the plan elevation of FIGURE 5, the plurality of poles is arranged in a circumferential row, thereby forming, in effect, a circumferential row of eleotromagnets. By using a single-phase alternating current supply for the windings 74, the magnetic field adjacent the planar surfaces of the pole pieces moves in a plane and in an arcuate direction. By placing the electrically conductive disk 50 or 51 adjacent the magnetic system, the moving magnetic field induces a current in the disk S0 or 51 and this current is then acted upon by the same field which produced it so that a force is exerted on the disk tending to move it in the same arcuate line.

Thus, it will be appreciated that each of the field structures 62 and its associated member 63 produces a traveling magnetic field through its corresponding disk 50 or 51 so that the respective disk 50 or 51 constitutes the rotor of the machine and a uniformly distributed force will be exerted over a comparatively large area of the disk 50 or 51 without direct mechanical contact so that the drive is independent of any mechanical speed changer or of any friction between belts and rollers used in conventional equipment. Accordingly, it is possible by effecting a suitable electric or electronic control of the magnetic system of such a motor to accomplish the functional demands required of cleaning equipment without utilizing the more complex conventional type mechanisms of machines heretofore provided.

In this regard, reference may now be advantageously made to the schematic circuit diagram of FIGURE 6. In FIGURE 6, two induction motor units are contemplated indicated generally at A and at B, the induction unit A being associated with the disk 51 for the drum or basket 14 and the unit B being associated with the disk 50 and the agitator shaft 20.

At the lower left-hand side of the drawing of FIGURE 6, there is shown connected to the hub 53 in comovable assembly a radially extending arm 80.

Attached to the frame of the washing machine, indicated diagrammatically in FIGURE 6 at F, there is provided two adjustably spaced limit switches 81 and 82. The limit switches 81 and 82 may be carried on suitable brackets as indicated at 83, thereby to effect an angular spaced relationship as indicated by the illustrative angle 84 and which angle is illustrated by the dotted line positions of the arm wherein the arm 80 is shown in engagement with an actuator button 86 on the limit switch 81 and an actuator button 87 on the limit switch 82.

The diagrammatically illustrated switch 8'1 has a movable switch element 88 movable between fixed contacts 89 and 90, while the diagrammatically shown switch 82 has a movable switch element 91 movable between fixed contacts 92 and 93.

It will be understood that the bracket 83 may be suitably adjusted through appropriate adjustment of an adjustment means 94, thereby to vary the angle 84 and hence the length of the agitator stroke.

Electric power from a conventional source of supply is tapped as at L1 and L2.

A conductor wire 96 connected to the terminal L1 leads to the movable switch element 88 of the limit switch 81. In this regard, it should be noted that both of the limit switches 81 and 82 are of the single pole, double throw type and in the solid line position of FIGURE 6, current passes from the conductor wire 96 through the movable switch element 88, through the contact 89 into a conductor wire 97, through the contact 93, the movable switch element 91, and into a conductor wire 98 electrically connected to a relay shown generally at 99. The conductor wire 100 connected to the other side of the relay leads back to the source terminal L2.

As soon as the trip bar or lever arm 80 engages one of the actuator buttons 86 or 87 of a corresponding limit switch 81 or 82, the relay 99 operates and thereby actuates a double pole, double throw switch indicated generally at 101. The switch 101 has movable switch elements 102 and 103 and in the full line position of FIG- URE 6 the elements 102 and 103 are shown engaged with contacts 104 and 106, respectively. In the dotted line position, the switch elements engage contacts 107 and 108.

It will be noted that the movable contacts 102 and 103 are connected by way of electrical conductors 4109 to one set of the windings 74a of the linear induction motor -unit B associated with the agitator, the windings of the other set being connected through electrical conductors 110 to the fixed contacts of switch 101 with a capacitor 111a being connected in series to provide a resultant voltage substantially out of phase with the line voltage.

The double pole, double throw switch 101 performs the function of reversing the polarity of the windings of the motor unit B, thereby reversing the action of the motor on the disk 50 and oscillating the agitator through a stroke determined by the size of the angle 84.

The circuit leading from the switch 101 is a firing circuit which includes silicon controlled rectiliers identified as SCR1 and SCR2. There is also provided a voltage regulator identified at 111 which takes the form of a diode connected in circuit with a full bridge shown generally at 112.

A timing control circuit including a unijunction transistor UJ T1 is provided for controlling the firing times of the silicon controlled rectifiers SCRl and SCRZ to control the amount of current supplied to the motor units A and B and thereby control the speed of operation thereof. In particular, parallel with the voltage regulator 111 and the power source, there is provided a fixed resistor 113 operating as a safety resistor. In series with the resistor 113 are contacts of a timer control illustrated in dotted lines and including contacts T1 and T2. In series with the timer contacts are provided variable resistors designated at 114 and 116, respectively.

In series with the variable resistors 114 and 116 the fixed resistance 113, a capacitor shown at 117 is provided and which is adapted to be charged on each of the half cycles.

In parallel with the circuitry thus provided, there is included the unijunction transistor shown generally at UJTl having its emitter connected in series with the capacitor 117 and also in series with the resistance 113 and the timer contacts T1 and T2 and the variable resistors 114 and 116. Resistances shown at 117a and 118 are connected in circuit with the collector of the unijunctional transistor UJT1.

Leading from that circuit, there are provided two separate lines including a conductor 119 and a series resistor 120 and a conductor 121 and a series resistor 122. The conductors 119 and 121 supply control signals to the gate electrodes of the rectiers SCR1 and SCR2. Conductors 123 and 124 are connected to the anodes of the rectifiers SCRI and SCR2 and to the center-tapped secondary of a transformer 126 having a primary connected across the line L1 and L2 as at 127 and 128. Another secondary 129 of the transformer 126 is connected to the bridge rectifier 112.

In operation, when a voltage appears across the voltage regulator 111, the capacitor 117 starts to charge according to a rate of charge determined by the variable resistors 114 or 116 as controlled through the sequentially controlled timer contacts T1 and T2. The variable resistors 114 and 116 are adjustable and by controlling the amount of time or frequency in which the capacitor 117 charges these resistors can be utilized to control the speed of agitation or centrifuging. By this method of frequency control, the agitation and centrifuging speeds can be effectively controlled.

When the capacitor 117 is sufficiently charged, it discharges through the emitter of the transistor UJT1, thereby firing the transistor UIT1 to develop a voltage puise across resistor 117a which is applied to the gate electrodes of the rectifiers SCR1 and SCR2. In accordance with the polarity of the alternating current at that instant, one or the other of the silicon control rectifiers will conduct to supply current through a double pole, double throw switch shown generally at 130 and to the switch 101 to the agitating motor unit B and then back through the switch 101 to the switch 130 and back to the transformer 126. In this regard, note that the switch 130 has an upper blade 131 movable between contacts 132 and 133 and also a lower blade 134 movable between contacts 136 and 137. The blade 134 is connected by means of a conductor 138 to a tap 139 on the secondary of the transformer 126, while the blade 131 is connected by means of a conductor 140 to the other components of the firing circuit.

On the next half cycle of the alternating current, the opposite silicon control rectifier will fire and a current fiow will be produced through the corresponding silicon control rectifier in the manner described above.

In a centrifuging cycle the blades 131 and 134 of the switch 130 are moved to the dotted line position. To effect that function, a mechanical linkage is shown at 141 actuated by a control knob 142 which can be placed on the control console of the machine for ready access by an operator. In the dotted line position, one of the variable resistors 114 and 116 will determine the speed of the spinning motor unit A and the same general sequence of operating events will be provided except that the windings of the spin motor unit` A will be energized through conductors 143 and 144 connected to the contacts 133 and 134, with a capacitor 144a being connected in series with one set of the windings to provide a resultant voltage substantially out of phase with the line voltage. In this circuitry, the reversing switch 101 is bypassed since operation of the spin motor unit A can be unidirectional.

As suggested hereinabove, the oscillatory motion of the agitator 29 is controlled by the corresponding movement of the lever arm and the engagement therewith of the actuator buttons 86 and 87 of the limit switches 81 and 82. For example, when the bar 80 engages the push button 87 of the limit switch 82 and causes the switch blade 91 to move to the dotted line position against the contact 92, the relay 99 is deenergized and the reversing switch 101 will be positioned so that the polarity of the magnetic field of the motor unit B will be in one direction. When the disk 50 moves and the arm or bar 80v travels to engage the other button 8-6 of the limit switch `81, the blade 88 will be moved to the dotted line position and will engage the contact 90, thereby again energizing the relay 99 whereupon the switch 101 will be reversed to reverse the polarity of the magnetic field. The motion of the bar 80 Within the confines of the limit switches 81 and 82, therefore, affords an oscillating motion of the agitator.

In order to effect a completely automatic operation of the device, the mechanical linkage 141 shown connected to the manual adjustment knob 142 can be operated by the presettable sequential controller 31 as embodied in the machine of FIGURE l or 48 as embodied in the machine of FIGURE 2. To illustrate that alternative in the schematic circuit diagram of FIGURE 6`, a program timer motor M is shown connected to the linkage 141 via the knob 142 and it will be understood that the motor M would be the motor of the presettable sequential control means 31 or 48.

It is further contemplated by the present invention that speeds could not only be varied electronically in the manner described hereinabove, but the relative radial positioning of the motor units A and B with respect to the disks 50 and 51 would effect an adjustment since positioning either of the motor units A and B closer to the shaft axis by varying the radial spacing dimension wou-ld also vary the torque exerted on the moving part.

Although various minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Laundry apparatus for Washing and centrifuging fab` rics in programmed sequence comprising, a rotary container for retaining the fabrics to be washed in the presence of a laundry fluid during a washing operation and to be centrifuged during a fluid extraction operation, agitating means positioned within said container for agitating said fabrics during said washing operation, a rotary disk of nonmagnetic, electrically-conductive material connected in driving relationship to said rotary container, an oscillatory disk of nonmagnetic, electrically-conductive material connected in driving relationship to said agitating means, arcuately shaped stators respectively positioned immediately adjacent each of said disks and having respective coplanar magnetic poles terminating in planes parallel to said disks, said disks including portions of reduced cross section immediately adjacent said arcuately shaped stators, circuit means for energizing said stators, said circuit means including polarity reversing switch means electrically connected to the stator positioned adja cent said oscillatory disk, a relay controlling actuation of said reversing switch means, a pair of limit switches electrically connected to said relay, a limit switch actuating arm rigidly connected to said oscillatory disk and engageable with said limit switches to thereby actuate said relay and said polarity reversing switches upon oscillatory movements of said oscillatory disk, agitate-centrifuge selector switch means connected to said circuit means and controlling the energizing of said polarity reversing switch means, a sequential program timer controlling the energization of said agitate-centrifuge selector switch means, circuit control means for supplying predetermined supply voltages to each of said stators, said circuit control means including a pair of silicon control rectiers each having a gating control, a timing control circuit connected to said gating controls and including a unijunction transistor and a R-C circuit including a charging capacitor and a pair of adjustable resistors, a series switch respectively connected to each of said resistors and controlled lby said program timer, said program timer selectively connecting one of said resistors in said timing control circuit during said washing operation and connecting the other of said resistors in said timing control circuit during said uid extraction operation, a D-C voltage source supplying said timing control circuit with a D-C voltage, and means for varying the resistance values of said resistors to vary the charging rate of said charging capacitor to control the firing of said unijunction transistor and the voltage supplied to said stators by said silicon control rectiers.

2. Laundry apparatus as dened in claim 1 and means for selectively adjusting the angular position of said limit switches, thereby to selectively vary the length of the agitating stroke.

3. Laundry apparatus as defined in claim 1 wherein said apparatus comprises a vertical axis machine having concentric shafts disposed on a vertical upright axis and interconnecting said rotary disk and said oscillatory disk to said agitating means and to said rotary container, respectively.

References Cited UNITED STATES PATENTS 3,152,462 10/1964 Elliott et al 68-12 3,152,463 10/1964 Sones et al. 68-12 3,184,933 5/1965 Gaugler 68-23 3,194,032 7/ 1965 Von Brimer 684-12 1,519,798 12/1924 Pilkington et al. 310-166 1,722,984 7/ 1929 Hendry 68-23 X 2,104,283 1/1938 Webster S10-39 2,105,514 1/1938 Welch. 2,225,407 12/ 1940 Bassett 68-12 2,897,387 7/1959 Welter 310-268 3,018,649 1/1962 Barbulesco et al 68-12 1,585,566 5/1926 Sindl 259-81 FOREIGN PATENTS 387,410 2/1933 Great Britain. 925,440 5/1963 Great Britain.

WILLIAM L. PRICE, Primary Examiner U.S. Cl. X.R. 68-23.7, 24 

1. LAUNDRY APPARATUS FOR WASHING AND CENTRIFUGING FABRICS IN PROGRAMMED SEQUENCE COMPRISING, A ROTARY CONTAINER FOR RETAINING THE FABRICS TO BE WASHED IN THE PRESENCE OF A LAUNDRY FLUID DURING A WASHING OPERATION AND TO BE CENTRIFUGED DURING A FLUID EXTRACTION OPERATION, AGITATING MEANS POSITIONED WITHIN SAID CONTAINER FOR AGITATING SAID FABRICS DURING SAID WASHING OPERATION, A ROTARY DISK OR NONMAGNETIC, ELECTRICALLY-CONDUCTIVE MATERIAL CONNECTED IN DRIVING RELATIONSHIP TO SAID ROTARY CONTAINER, AN OSCILLATORY DISK OF NONMAGNETIC, ELECTRICALLY-CONDUCTIVE MATERIAL CONNECTED IN DRIVING RELATIONSHIP TO SAID AGITATING MEANS, ARCUATELY SHAPED STATORS RESPECTIVELY POSITIONED IMMEDIATELY ADJACENT EACH OF SAID DISKS AND HAVING RESPECTIVE COPLANAR MAGNETIC POLES TERMINATING IN PLANES PARALLEL TO SAID DISKS, SAID DISKS INCLUDING PORTIONS OF REDUCED CROSS SECTION IMMEDIATELY ADJACENT SAID ARCUATELY SHAPED STATORS, CIRCUIT MEANS FOR ENERGIZING SAID STATORS, SAID CIRCUIT MEANS INCLUDING POLARITY REVERSING SWITCH MEANS ELECTRICALLY CONNECTED TO THE STATOR POSITIONED ADJACENT SAID OSCILLATORY DISK, A RELAY CONTROLLING ACTUATION OF SAID REVERSING SWITCH MEANS, A PAIR OF LIMIT SWITCHES ELECTRICALLY CONNECTED TO SAID RELAY, A LIMIT SWITCH ACTUATING ARM RIGIDLY CONNECTED TO SAID OSCILLATORY DISK AND ENGAGEABLE WITH SAID LIMIT SWITCHES TO THEREBY ACTUATE SAID RELAY AND SAID POLARITY REVERSING SWITCHES UPON OSCILLATORY MOVEMENTS OF SAID OSCILLATORY DISK, AGITATE-CENTRIFUGE SELECTOR SWITCH MEANS CONNECTED TO SAID CIRCUIT MEANS AND CONTROLLING THE ENERGIZING TO SAID POLARITY REVERSING SWITCH MEANS, A SEQUENTIAL PROGRAM TIMER CONTROLLING THE ENERGIZATION OF SAID AGITATE-CENTRIFUGE SELECTOR SWITCH MEANS, CIRCUIT CONTROL MEANS FOR SUPPLYING PREDETERMINED SUPPLY VOLTAGES TO EACH OF SAID STATORS, SAID CIRCUIT CONTROL MEANS INCLUDING A PAIR OF SILICON CONTROL RECTIFIERS EACH HAVING A GATING CONTROL, A TIMING CONTROL CIRCUIT CONNECTED TO SAID GATING CONTROLS AND INCLUDING A UNIJUNCTION TRANSISTOR AND A R-C CIRCUIT INCLUDING A CHARGING CAPACITOR AND A PAIR OF ADJUSTABLE RESISTORS, A SERIES SWITCH RESPECTIVELY CONNECTED TO EACH OF SAID RESISTORS AND CONTROLLED BY SAID PROGRAM TIMER, SAID PROGRAM TIMER SELECTIVELY CONNECTING ONE OF SEAID RESISTORS IN SAID TIMING CONTROL CIRCUIT DURING SAID WASHING OPERATION AND CONNECTING THE OTHER OF SAID RESISTORS IN SAID TIMING CONTROL CIRCUIT DURING SAID FLUID EXTRACTION OPERATION, A D-C VOLTAGE SOURCE SUPPLYING SAID TIMING CONTROL CIRCUIT WITH A D-C VOLTAGE, AND MEANS FOR VARYING THE RESISTANCE VALUES OF SAID RESISTORS TO VARY THE CHARGING RATE OF SAID CHARGING CAPACITOR TO CONTROL THE FIRING OF SAID UNIJUNCTION TRANSISTOR AND THE VOLTAGE SUPPLIED TO SAID STATORS BY SAID SILICON CONTROL RECTIFIERS. 